Channel Five has hailed the "Natasha effect" on its early evening news bulletin, saying the programme has seen its ratings grow by 72% since Natasha Kaplinksy took on presenting duties a month ago.
Five hired Kaplinksy from the BBC last year on a £1m-a-year deal, making her the highest paid newsreader in the UK.
The commercial broadcaster said that during the first month on air the 5pm broadcast of Five News with Natasha Kaplinsky, which launched on February 18, averaged 847,000 viewers and a 6.7% share among all viewers between then and March 14.
Five added that share had grown 72% compared with the first six weeks of the year, when the previous 5.30pm bulletin pulled in an average audience share of 3.9%.
The 5pm bulletin had also grown its audience share 69% compared with the 5.30pm programme's performance across the whole of 2007, when it attracted an average share of 4%, the broadcaster said.
Five added that share among 16- to 34-year-olds was up 83% on 2007, to 6.2%, while the share of ABC1 viewers was up 122% to 4%.
The 7pm Five News with Natasha Kaplinksy has also seen a ratings boost, although not by such a large degree, averaging 399,000 viewers and a 1.9% share in the month since February 18.
This was a 43% increase on the first six weeks of the year and 31% up on the whole of 2007, Five said.
The Five senior programme controller, Chris Shaw, said: "When we relaunched five weeks ago our first Five News with Natasha Kaplinsky doubled its audience with a million viewers, which was fantastic, but we worried that it might just be one-off driven by our "Natasha in jeans" marketing campaign.
"There is, however, apparently a 'Natasha effect'. We already knew from internal BBC research data that she was the best recognised female newsreader in the UK and she obviously has a profile outside TV news as well but we certainly didn't expect this extraordinary jump in viewing figures.
"Now five weeks on we can see that she has had a permanent affect on our viewing figures, fully vindicating our decision to bring her over from the BBC to Five."
He added: "Natasha is able to bring something entirely new and fresh to television news. She combines authority with true warmth, and accessibility and these qualities have really been allowed to blossom on Five."
The editor of Five News, David Kermode, also Kaplinsky's editor on BBC Breakfast, said: "She has a very broad mass appeal but she's also working on a show which combines the best qualities of news programmes and daytime television. I don't think any other network news programme have pulled that off."
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